AC Milan strengthened their bid for an 18th Serie A title thanks to a win over struggling Sampdoria as a Clarence Seedorf free-kick, an Antonio Cassano penalty and a Robinho header secured all three points at the San Siro. The league leaders started strongly as Pato won a corner in the first minute which Ignazio Abate should have done better with, before Kevin-Prince Boateng shot over. Things took a downwards step for the home side, however, when goalkeeper Christian Abbiati was forced to be replaced by Marco Amelia, but this didn’t stop Milan as minutes later veteran midfielder Seedorf gave his side the lead from a free-kick which swerved across the floor and into the bottom corner. Neither side managed to create a chance for the majority of the rest of the half although there were concerns of the hosts when Alexandre Pato pulled up with an apparent hamstring injury, forcing Massimiliano Allegri to replace him with Cassano. In the opening minutes of the second period, Robinho put an easy chance high and wide after great play from Cassano. In the 53rd minute, Milan won a controversial penalty. Mario Yepes headed it against an arm, the referee blew up, and Cassano finished it, giving Gianluca Curci no chance in the Sampdoria goal. Seven minutes later, the points belonged to Milan. Cassano chipped over a cross, leaving Robinho to head in from point-blank range with Curci stranded. The goal killed what little resistance the visitors posed and AC Milan were able to pass the ball about at will, and it seemed only a matter of time until they would add to their already convincing lead. Seedorf scooped it over from a volley when he only had the keeper to beat, while Mario Yepes put a free header wide from a Gianluca Zambrotta cross. Andrea Pirlo was introduced in place of Mark van Bommel, and Cassano forced a great save from Curci. Cassano missed another golden opportunity to add a fourth after a volley that flew over when it was easier to score and AC Milan were not to have their showpiece finish. It mattered little to them, however, as the result saw them extend their lead over Napoli at the top of Serie A to six points.